And I'm Melissa Block. On the biggest story of the day, one of the biggest of the year, two leading television news channels got it wrong. CNN and Fox News mistakenly and repeatedly told viewers that the linchpin of the health care law had just been struck down by the Supreme Court. NPR media correspondent David Folkenflik breaks down the reporting breakdown.

DAVID FOLKENFLIK, BYLINE: It's as though the journalistic adage was get the story first, then get it right.

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KATE BOLDUAN: ...the opinion. But I want to bring you the breaking news that according to producer Bill Mears, the individual mandate is not a valid of...

(SOUNDBITE OF CHEERING)

BOLDUAN: ...not a valid exercise of the Commerce Clause. So it appears as if the Supreme Court justices have struck down the individual mandate, the centerpiece of the health care legislation.

FOLKENFLIK: That was CNN's Kate Bolduan at 10:07 a.m. Eastern time today amid a raucous scene outside the court. Anchor Wolf Blitzer picked up the scent.

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WOLF BLITZER: That would be history unfolding right now. We're going to get a lot more information. This is just the initial headline that we're getting from inside the Supreme Court.

FOLKENFLIK: Or not the headline at all. Over on Fox News, Bill Hemmer said much the same.

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BILL HEMMER: The individual mandate has been ruled unconstitutional.

FOLKENFLIK: But pretty soon, Hemmer invoked a new doctrine as he talked to Fox News' Megyn Kelly.

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HEMMER: We talked about the fog of law. And to our viewers at home, be patient with us as we work through this. Megyn, you're seeing something now.

MEGYN KELLY: Wait, we're getting conflicting information.

HEMMER: What is that?

KELLY: We're getting conflicting information.

FOLKENFLIK: And for that matter, so was CNN. Over to you, Wolf.

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BLITZER: If, in fact, that's the final word on the individual mandate, it could be a little bit more complicated.

FOLKENFLIK: As indeed it was. Fox's Kelly cited scotusblog.com as she first switched the call. And some minutes later, CNN's Bolduan reversed herself too.

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BOLDUAN: What we are reading here is that the individual mandate may be upheld under a narrow reading of the Constitution, not under the Commerce Clause. We're talking about the taxing clause, Wolf. Very...

FOLKENFLIK: Fox remedied but didn't quite apologize or call it a correction on air. CNN took its time but ultimately apologized and posted a full correction. So what went wrong? Well, on page two, the ruling found the individual mandate was not constitutional under the Commerce Clause, but a page later, it upheld the mandate as a permissible tax. The two networks didn't wait to absorb page three. NPR political talk show host Diane Rehm, relying on CNN, got it wrong too during her show, though NPR's own reporting got it right. But for that matter, President Obama was also fooled. He was watching both CNN and Fox. David Folkenflik, NPR News. Transcript provided by NPR, Copyright NPR.